A typical sewing machine has three principal components which contact the fabric that is being sewn, namely the throat base, the hopping foot and the needle. The fabric rests upon and is positioned by the throat base, which is a horizontal flat surface having a penetration which allows the needle to push completely through the bottom of the fabric that is being sewn and interact with a bobbin is beneath the throat base, and which, with the needle, provides for completion of the stitching operation. The needle, with thread fed in a controlled fashion by other components of the sewing machine, performs the stitching operation through interaction with the bobbin beneath the throat base. The hopping foot presses down on top of the fabric keeping the fabric positioned on the throat base and preventing separation and relative movement of the layers of fabric that are being sewn. A hopping foot is typically spring loaded, providing for fabric thickness variations and progression of the fabric as it is being sewn. The needle is secured by and driven by a needle bar which is attached to and controlled by the needle drive system of the sewing machine.
A hopping foot is normally positioned either behind the needle bar, that is between the operator and the needle bar, or laterally from the needle bar, that is into the throat of the sewing machine. The throat of the sewing machine is the space between the needle bar and the vertical structure of the sewing machine. The dimensions of the throat are particularly important in sewing operations such as quilting, as it determines how much fabric can be positioned in the throat and therefore how far laterally into the fabric the sewing operation can progress.
There are several problems or limitations with traditional hopping foot design with the hopping foot being positioned either behind or laterally from the needle bar. Either the hopping foot imposes limitations on the visibility of the needle bar in the sewing operation, or it reduces the throat space of the sewing machine by reducing the usable throat width by the separation distance between the needle bar and the hopping foot. For the latter, this is typically approximately one inch. As indicated above, the width of the throat of a sewing machine that is available for fabric accumulation is particularly important for machine quilting, because, as a quilt is sewn, the sewn area of the quilt is rolled on a rail which passes through the throat of the sewing machine. Therefore, a sewing machine with more available throat width provides for an accumulation of a greater amount of fabric.
It is therefore an object of the present invention to provide a hopping foot that provides better visibility of a needle bar during fabric placement and sewing.
It is a further object of the present invention to provide a hopping foot that provides for increased throat space for the accumulation of fabric.